fix clang with c++_static

[waruqi]

#7442

[gemini-code-assist]

Code Review

This pull request modifies the Clang tool module to remove a redundant assignment to the c++_static map when a static runtime is used. A review comment suggests refining the conditional check to specifically target stdc++_static, which would improve precision and provide better safety against null values.

[gemini-code-assist]

The condition runtime:endswith("_static") matches both c++_static and stdc++_static. Since the logic inside this block now only updates maps["stdc++_static"], it is more precise to check for runtime == "stdc++_static". This avoids unnecessary calls to _has_static_libstdcxx(self) (which may involve compiler flag detection) when runtime is c++_static. Additionally, using == is safer as it prevents a potential crash if runtime is nil, whereas endswith would throw an error.

                if runtime == "stdc++_static" and _has_static_libstdcxx(self) then